Over the last few years, several 3-wheeled strollers have entered the market claiming various "all-terrain" features and/or recreational and fitness related capabilities.
All of these designs benefit from the inherent stability of tripodal wheeled contact points over variable terrain. But several salient structural limitations common to all of them limits the quality and versatility of their performance.
The numerous modes of use that modern stroller designs attempt to satisfy have branched into several specialized areas of usefulness. Two primary fields of use are: Street or "urban" use, with an emphasis on light, compact and collapsible design; and "rural" or recreational and fitness/jogging/all-terrain use, with an emphasis on larger wheels and tripodal wheel configurations, to mitigate the effects of uneven or unpaved ground.
The present invention incorporates many of the super light and compact folding features of traditional "urban" stroller and buggy designs, with the durable and mobility enhancing advantages of the so-called "jogging" or "all-terrain" strollers, which are more suitable in suburban and rural environments, into a single unitary design. This Urban and All-Terrain Stroller not only brings these fields of use together, but also substantially improves vehicle performance in both it's urban/street and recreational/rural modes.
U.S. Pat. Nos. 4,953,880 (Sudakoff), 5,029,891 (Jacobs), 5,123,670 (Chen), 5,176,395 (Garforth-Bles), 5,224,720 (Chaw), 5,076,599 (Lockett), and 5,188,389 (Baechler), all embody three-wheeled strollers. All have chassis designs with similar support frameworks that define a rigid triangular or T-shaped structural "plane," parallel to the ground, the height or ground clearance of which is generally determined by the height of the wheel axis above the ground. They also have a solid axle, in the above-stated plane, along the axis generally defined by the two rear wheels.
These common features share distinct limitations: 1) the chassis' ground clearance is limited by the height of the wheel axis, necessitating a larger wheel to provide adequate ground clearance; 2) the total center of gravity of a seated child is moved upward, because all cross supports and framing must occur above the defining plane determined by the height of the wheel axis (necessitating a larger vehicle envelope, and a longer and/or broader "foot-print" of contact points with the ground, to achieve desired stability), and; 3) a solid, uninterrupted structural element or "axle" between the two rear wheels precludes the possibility of having all three wheels, in a collapsed mode, aligned along a single axis, which is most desirable for both maximal collapsing performance, and ease of mobility, transport and storage while stroller is collapsed.
While attempting to comprehensively address the very specific and narrow design considerations related to recreational, fitness, and "all-terrain" stroller use, these strollers actually do so in a way that limits their utility to their own specialty design niche, precluding practical use in all-purpose and/or urban applications. These strollers all incorporate similar design short-comings, with minor changes, evidencing a failure to embark on a comprehensive design revision and functional solution.
It has long been recognized that accidental collapse, and the scissoring and pinching action associated with collapsing strollers, are two of the most injury and liability prone aspects of all stroller designs, but very little has been done to comprehensively address these significant flaws.
Further, most strollers that can provide both upright and reclined seat positions do so in a way that necessitates moving the load center of gravity outward, usually toward the rear, increasingly moving the load weight away from the vehicle's and vehicle load's center of gravity. In the preferred embodiment of the present vehicle, the reclined position is achieved by shifting the child's weight slightly forward and down, increasing the vehicle and vehicle load stability by moving the weight further inside the vehicle envelope, and farther within the "footprint" of the three wheels.
Accordingly, several objects and advantages of the present invention specifically address the broad failures of preexisting three-wheel designs while incorporating numerous other functional advantages that will become apparent from the following description of a preferred embodiment.